Electromagnetic bell



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jam@ l? Patented dan. l, 1924-.

lfflltll WILLIAM H. BRADLEY, OF SHELBY, CHIS, ASSGNOR TO THE AUTOCALLCOMPANY, 0F SHELBY, OHIO, A CORIORATIGN OF OHIO.

ELECTROMAGNETIC BELL.

Application filed December 26, 1918.

T 0 all whom t may concern: Y

Be it lrnown that I, WILLIAM I-I. BRADLEY, a citizen of the UnitedStates, and a resident of Shelby, county of Richland, and State of Ohio,have invented a new and useful Improvement in Electromagnetic Bells, ofwhich the following is a specification, the principle of the inventionbeing herein eX- plained and the best ymode in which I have contemplatedapplying that principle, so as to distinguish it from other inventions.

The object of the present invention is the provision of a bell of thetype indicated, which will beV simple and compact in construction andinvolve a minimum of operative parts, whereby the bell is renderedspecially suitable for use in call and alarm systems. A further objectis to arrange the parts so that the electro-magnet and armature may notonly be safely housed, but so disposed that moisture collecting eitheron the housing or on the gongv cannot readily enter within such housing.

To the accomplishment of the foregoing and related ends, said invention,then, consists of the means hereinafter fully described and particularlypointed out in the claims, the annexed drawing and the followingdescription setting forth inV detail certainl mechanism embodying theinvention, such disclosed means constituting, however, but one ofvarious mechanical forms in which the principle of the invention may beused.

In said annexed drawing Fig. 1 is a front elevation of my improved bell,with a portion of the casing broken away or shown in section; Fig. 2 isa vertical transverse section of the bell taken on the plane indicatedby the line 2-2, Fig. 1 and Fig. 3 is a horizontal transverse section ona somewhat reduced scale, talren on the plane indicated by the line 3--3, Fig. 2.

The various operative parts of the bell are all carried on a back orbase plate 1, preferably of metal, from the upper portion of whichprojects a deep integral flange 2 that forms the side walls of thecasing, in which the electro-magnet 3 and larmature 4 are housed. Aplate 5 secured to the face of this side wall by means of screws (seeFigs. 2 and 3) completes such housing. The gong 6 is carried on abracket 7 attached to the lower portion of the back or base plate bymeans of the long bolt 8, that secures the gong to Serial No. 268,236.

said bracket, and a supplemental shorter bolt 9 passing through adepending lip 1() on the bracket. The heads of these bolts are held in avertical slot 11 in the portion of the base plate referred to, whereby acertain limited amount of adjustmentof the gong in a correspondingdirection is rendered possible; and1 if desired to accommodate a largersizeigong than that illustrated in the several figures of the drawing,the position of the bracket 7 may be reversed, so thatthe lip 10projects upwardly, and the axis of the gong brought to coincideapproximately with the a-Xis of the shorter bolt, as illustrated in thefigures in question. By the foregoing means, gongs of various sizes maybe used without substitution of other parts.

The electro-magnet 3, which is of more or less familiar construction, issecured to the portion of the base plate'enclosed by the side walls 2previously described through the medium of short studs or lugs 15projecting from such plate. As shown in Fig. 2, the core of the magnetis of laminated construction, as is also the movable armature 4,although either or both may be of solid construction, if desired. In theillustrated construction, the armature comprises a plurality ofintermediate plates and two side plates of somewhat greater length,whereby they are caused to project at each end, solidly rivetedtogether, and in addition to the rivets 16, that serve this purpose,other rivets or pins 16a pass through such ends, so as to be clear ofthe intermediate plates, as shown in Fig. 3. One such rivet 16a (the oneat the right-hand in the position of parts shown in Fig. 1) is pivotallyheld in a lug 17, that projects inwardly from a plate 18 through anaperture 19 in the corresponding side wall of the casing andtitsabetween the side members of the armature. Plate 18 is detachablysecured to such side wall, so that upon loosening same the armature canbe withdrayvn from the casing or inserted, as may be desired.

The opposite side wall of the casing is formed with a similar aperture2O likewise covered by a plate 2l detachably secured to such wall, buthaving the form of a hollow boss, in which suitable transversely alignedbearings are formed for an oscillatory spindle 22. Keyed orpinned to theportion ot this spindle lying within the boss, is a short lcv arm 28 otthe form best shown in Fig. 1, which projects through the adjacentaperture into engagement with the'pin 16a on the tree end' 'o" thearmature 4; while on the forward end oit the spindle, which etttendssome distance through the boss, is similarly keyed or pinned a strikeror hammer arm 2A, the tree end oi" which is -formed with an enlargedhead and lies in the proper plane to strike the edge of the gong 6 fromwithin, when sucn'gong is secured in proper position on the base plate,in a fashion hereinbefore described.

rlhe armature and striker-arm are thus seen to lie between the gong andelectromagnet, transversely of a line passing through their axes, thestriker-arm being pivotally attached to the base on one side of suchline and the armature on the other.

The weight ot' the striker is sufficient normally to depress the sameinto the position shown in Figs. 1 and 2, in which position the armatured is clear or" the magnet core, but upon .the electro-magnet 3 beingenergized, said armature is drawn upwardly against the core, whereby itsfree end, acting on the short arm 23 on the spindle 22, raises thestriker head into contact with the gong, so as to sound the. latter.

rihe `operation ot mygimproved bell has been suiiiciently indicated inconnection with the description ot the several parts. It should,however, be specially noted that, as illustrated in Figs. 2 and 3, theelectro magnet and armature, as well V'as the electrical connectionswiththe former, are entirely included within the casing formed by the iiange2 and cover plate `5; yet the armature, as well as the spindle whichcarries the striker, are so mounted as to render them both readilyaccessible, not only for the purpose of assembly, but also for eX-amination and repair should this become necessary in the course of useof the bell. Furthermore, such adjustments are provided, particularlyT:tor the gong, as render the bell capable of use under a Wide variety otconditions. Finally, the gong, being disposed not only whdlly withoutthe cas-v ing, in which the electro-magnet and other operative parts arehoused, but below the same, it is rendered impossible tor moisture tocollect on suchy gong, as it is apt to do in damp location-s,and,ldripping therefrom, to tind its way into the interior of thecasing.

Other modes of applying the principle of my invention may be employedinstead 'of the one explained, change being made 'as rethe mechanismherein disclosed, provided the means stated by any of the followingclaimsor the equivalent of such stated means be employed.

l therefore particularly pointV ont and distinctly claim as my invention1- 1. In a device of the character described, the combination of asuitable base, a gong and an electro-magnet mounted'thereon, astriker-arm Ylorsaid gong, and an armature for Vsaid electro-magnetoperatively connested with said striker-arm, the latter and saidnrmaturehaving pivots disposed on opposite sides oit saidbase and located in aplane extending transversely at right angles to a line passing throughthe axes of said gong and electro-magnet, and the freer end of one oi'said members extending toward the pivoted end of the'other,respectively.

p 2. In a Vdevice ot the character described, the combination oit' avsuitable base, a gong and an electro-magnet mounted thereon, the latterabove the former, side-walls and a cover-plate encasing saidelectro-magnet, apertures in the same horizontal .plane in oppositeside-walls, detachable plates covering such apertures, anda striker-armand armature pivotally .attached at their outer ends to said`rdetachable plates, respectively, and each independently removablelfromsaid casing, the inner end of said armature being unattachedl to butoperatively associated with said strikenarm.

p 3. Inra device of the character described, the combination of asuitable base, a gong and an electro-magnet.mounted thereon, the latterabove the former, side-,walls and a cover-plate. encasing saidelectro-magnet, apertures in opposite side-walls, Adetachable platescovering such apertures, an armature for said electro-magnet pivotallyattached at one end to one of said detachable plates and removabletherewith from said encasing side-wall, a spindle voscillatory inthevother detachable plate and removable therewith from said encasingside-wall, a'lever-arm on said spindle llying within said cover-plateand adapted to be directly engaged by the free end of said armature, anda striker for saidgoiig. attached at one end to said spindle and lyingwithout said cover-plate. l

4. In a device of the character described the 1combination of a suitablebase having an elongated slot adjacent one end, a bellsupporting brackethaving an elevated standard with an integral lateral eXtension'at itsfoot` the base of said bracket being adapted to slidingly engage theedges of lthe slotted portion of the base with the standard disposed ateither end oit said slot, a bolt adapted to'bev engaged with the baseand the lateral extension o1" the bracket, and a second boltV associatedwith said standard and secured to; said basca-nd bell.

ySigned by me, this 23d day of December,

1918. WILLIAM H. BRADLEY.l

